Cyclic perfluoropolyether

ABSTRACT

Novel hydroxy containing fluorovinyl ethers, polymers of hydroxy containing fluorovinyl ethers, novel cyclic ethers, copolymers of selected hydroxy containing fluorovinyl ethers, a process for reducing ester containing fluorovinyl compounds to the corresponding alcohol with borohydrides, and a process for polymerizing hydroxy containing fluorovinyl ethers are disclosed.

This application is a divisional application of Ser. No. 713,911 (nowU.S. Pat. No. 5,134,211), filed Jun. 12, 1991, which is aContinuation-In-Part of U.S. Ser. No. 592,172 (now U.S. Pat. No.5,059,720), filed Oct. 9, 1990, which is a divisional application ofSer. No. 473,083 (now U.S. Pat. No. 4,982,009), filed on Jan. 31, 1990.

A process for reducing ester containing fluorovinyl compounds to thecorresponding alcohol with alkali metal borohydrides, selected novelhydroxy containing fluorovinyl ethers, novel cyclic ethers, novelpolymers of hydroxy containing fluorovinyl ethers, a process for makingsuch polymers and novel copolymers of selected hydroxy containingfluorovinyl ethers are provided.

BACKGROUND OF THE INVENTION

Japanese Patent 88002418 reports the synthesis of7,7-dihydro-7-hydroxy(perfluoro-3-oxahepten-1) by chlorinating themethyl ester of perfluoro(3-oxa-1-heptenoic acid), reduction of thechlorinated product with NaBH₄ to give the corresponding alcohol, andthen reaction of the alcohol with zinc metal to regenerate the vinylether, which is the desired product. It is reported that this compoundcan be free radically copolymerized with at least one other fluorinatedmonomer, and optionally non-fluroinated monomers, to form usefulpolymers.

U.S. Pat. No. 4,564,717 reports the synthesis of compounds of theformula CF₂ ═CF(CF₂)_(m) (CH₂)_(n) OH wherein m is an integer from 0 to10 and n is an integer of 1 to 4. Among the methods of preparationdescribed, is the reduction of the compound CF₂ X¹ CFX² CF₂ COOR (sic)wherein R is alkyl and X¹ and X² are chlorine or bromine, by variousreducing agents including alkali metal borohydrides. The olefin is thenproduced by dehalogenation of the alcohol with a metal such as zinc. Inessence, in both this and the previous reference, the double bond hasbeen "protected" by halogenating it (with chlorine or bromine) beforethe reduction step, and dehalogenating after the reduction step.

European Patent Application 135,917 discloses copolymers of vinylidenefluoride with a compound of the formula CF₂ ═CF(CF₂)_(m) (CH₂)_(n) OHwhere m is 0 to 10 and n is 1-4, and optionally another fluorinatedtermonomer. Polymers of hydroxy containing fluorovinyl ethers are notmentioned.

European Patent Application 199,138 reports preparation andpolymerization (with other fluorine containing olefins) of the compoundCF₂ ═CFO(CF₂ CFYO)_(n) (CF₂ CF₂ CH₂ O)_(m) CF₂ CF₂ CH₂ X, wherein X ishydrogen or halogen, Y is fluorine or -CF₃, m is an integer of 0 to 5and n is 0, 1 or 2. No mention is made of a hydroxy group being present.

It is one object of the present invention to provide a simplified methodfor the production of hydroxy containing fluorovinyl compounds by thealkali metal borohydride reduction on the corresponding esters. It is anadditional object to conduct the reduction process so protection of thedouble bond, as by halogenation, is unnecessary.

A further object of the invention is to homopolymerize hydroxycontaining fluorovinyl ethers using anionic catalysts. It is anadditional object to disclose polymers resulting from the polymerizationof hydroxy containing fluorovinyl ethers.

Finally, it is also an objective of this invention to provide certainnovel hydroxy containing fluorovinyl ethers and their copolymers withselected monomers.

These and other objects are achieved by the invention disclosed in thebelow specification and in the appended claims.

SUMMARY OF THE INVENTION

This invention concerns a process for the production of hydroxycontaining fluorovinyl compounds, comprising, contacting in a solvent analkali metal borohydride with a compound of the formula CF₂ ═CFR¹ CO₂ R²wherein R¹ is a covalent bond, a perfluoroalkylene group and --OR³--wherein R³ is a perfluoroalkylene group, and R² is hydrocarbyl orsubstituted hydrocarbyl. This invention further concerns hydroxycontaining fluorovinyl ethers of the formula CF₂ ═CF[OCF₂ CF(CF₃)]_(n)(O)_(p) (CF₂)_(m) CH₂ OH wherein p is 0 or 1, m is 0 to 10 and n is 1 to20, provided that when m is 0, p is 0, and further provided that when mis greater than 0, p is 1. Also disclosed is a process for polymerizinghydroxy containing fluorovinyl ethers, comprising, contacting a selectedcatalyst with one or more hydroxy fluorovinyl ethers of the formula CF₂═CFOR⁴ CF₂ CH₂ OH, wherein R.sup. 4 is perfluoroalkylene. A polymerconsisting essentially of the repeat formula --[CF₂ CFHOR⁴ CF₂ CH₂ O]--,wherein R⁴ is perfluoroalkylene. Also disclosed is a copolymercontaining the hydroxy containing repeat unit ##STR1## wherein p is 0 or1, m is 0 to 10 and n is 1 to 20, provided that when m is 0, p is 0, andfurther provided that when m is greater than 0, p is 1, with otherselected repeat units.

This invention also concerns cyclic ethers of the formula ##STR2##wherein R⁴ is perfluoroalkylene and q is 2, 3 or 4.

DETAILS OF THE INVENTION

In accordance with the present invention, there is provided a processfor the production of hydroxy containing fluorovinyl compounds,comprising, contacting in a solvent an alkali metal borohydride with acompound of the formula CF₂ ═CFR¹ CO₂ R² wherein R¹ is selected from acovalent bond, a perfluoroalkylene group and --OR³ --wherein R³ is aperfluoroalkylene group, and R² is hydrocarbyl or substitutedhydrocarbyl.

By "perfluoroalkylene group" herein is meant a bivalent saturatedradical regarded as derived from a perfluorinated alkane by the removalof two fluorine atoms from different carbon atoms. The"perfluoroalkylene group" may also contain oxygen atoms between alkylenesegments, to form one or more ether groups in each perfluoroalkylenegroup.

By "substituted hydrocarbyl" herein is meant any substituent in ahydrocarbyl group that will not interfere with the reduction reaction.However, even substituents that react with the alkali metal borohydridesmay be present, provided enough borohydride is added to reduce the esterto the alcohol.

Preferred alkali metal borohydrides are lithium borohydride, sodiumborohydride and potassium borohydride. The molar ratio of borohydride toester is about 0.3 to about 1.2, preferably about 0.4 to about 0.8.

It is preferred that the solvent is an alcohol. Preferred alcohols aremethanol and ethanol.

The process is carried out at about -10° to about +30° C., preferablyabout 0° to about 15° C. and most preferably about 5° to about 10° C.External cooling may be needed to maintain the correct temperature.

Any substantial amount of water should be excluded from the reaction,and it is convenient to carry out the reaction under an inert atmospheresuch as nitrogen, in order to exclude moisture. Starting materialsshould be substantially dry. Agitation is preferred during the reaction,and it is preferred if the agitation is vigorous for efficient mixing.

Products may be isolated by standard techniques well known to thoseskilled in the art, such as distillation. Such techniques areillustrated in the Examples.

Typical procedures for preparing compounds of the formula CF₂ ═CFR¹ CO₂R² are found U.S. Pat. No. 4,275,226; R. Sullivan in J. Org. Chem., vol.34, pp. 1841-1844 (1969); U.S. Pat. No. 4,281,092; and U.S. Pat. No.4,138,426.

In preferred embodiments R¹ is --OR³ --, wherein R³ is --(CF₂)_(y) --,wherein y is 2 to 10; or R¹ is --OR³ --wherein R³ is --[CF₂CF(CF₃)O]_(x) (CF₂)_(z) --, wherein z is 1 to 10 and x is 1 to 20; or R¹is perfluoroalkylene; or R¹ is a covalent bond. In an especiallypreferred embodiments R¹ is --(CF₂)_(q) --wherein q is 1 to 10; or x is1 and z is 2. In a preferred embodiment of the process R² is alkyl, andit is especially preferred if R² is alkyl in combination with any of thepreferred embodiments of R¹. Unless otherwise noted, all numericalranges that refer to chemical formulas herein, represent integersthroughout those particular ranges, and not fractional values.

The hydroxy containing fluorovinyl compounds produced by the aboveprocess are useful as monomers in polymerization, and may be homo- orcopolymerized (infra).

Also disclosed is a process for polymerizing hydroxy containingfluorovinyl ethers, comprising, contacting a base or another compoundselected from the group consisting ofbis(triphenylphosphoranylidene)-ammonium chloride, an alkali metalcarbonate, R¹ ₄ NCl, (R¹ ₄ N)₂ CO₃, R¹ ₄ NHCO₃, and cesium fluoride,with one or more hydroxy fluorovinyl ethers of the formula CF₂ ═CFOR⁴CF₂ CH₂ OH, wherein R⁴ is perfluoroalkylene, and each R¹ isindependently alkyl.

The polymers and cyclic ethers produced by this process are describedbelow. By the word "polymerizing" in the paragraph immediately above ismeant the production of linear polymeric or cyclic ethers. The formationof the cyclic ethers is favored by the use of solvents, and inparticular, relatively dilute solutions during the polymerization.Linear polymer formation is favored by concentrated monomer solutions,and in particular, carrying out the process without solvent.

When a base is used, the polymerization process is preferably carriedout in a solvent, preferably a polar but nonprotic solvent. Suchsolvents are well known to those skilled in the art, and include, butare not limited to N,N-dimethylformamide, dimethylsulfoxide,N,N-dimethylacetamide, tetrahydrofuran, the glymes, etc.N,N-dimethylformamide is preferred. Protic solvents, particularly thosethat contain a proton more acidic than the hydroxy group in the hydroxycontaining fluorovinyl ethers should be avoided. The solvents, andindeed all starting materials should be substantially free of water.

The base used in the process should be one whose conjugate acid is lessacidic than the hydroxy proton in the hydroxy containing fluorovinylether. The base should also be at least slightly soluble in the reactionmedium, so that reaction may be affected. Such bases are well known tothose skilled in the art, and include, but are not limited to alkalimetal alkoxides, alkali metal hydrides, amines, etc. Alkali metalalkoxides and hydrides are preferred, and potassium t-butoxide isespecially preferred. The molar ratio of hydroxy containing fluorovinylether to base is about 5 to about 200, preferably about 8 to about 50,most preferably about 10 to about 25.

When a base is used, the process is run at a temperature of about -10°to about +100° C., preferably about 0° to about 50° C., most preferablyabout 10° to about 30° C. Agitation is of the reaction mass preferred,preferred to mix separate phases.

It is believed that the base or "another compound"[bis(triphenylphosphoranylidene)ammonium chloride, an alkali metalcarbonate, R¹ ₄ NCl, (R¹ ₄ N)₂ CO₃, R¹ ₄ NHCO₃, or cesium fluoride]actas catalysts for the polymerization process. In order to achieve maximummolecular weights of the polymer produced, and in particular to avoidsignificant production of cyclic dimer, trimer, etc., it is preferred ifthe catalyst is not a base.

Preferred other compounds are bis(triphenylphos-phoranylidene)ammoniumchloride, R¹ ₄ NCl, wherein each R¹ is independently alkyl containing 1to 6 carbon atoms, cesium fluoride, cesium carbonate and potassiumcarbonate. When other compounds are used as catalysts, and to obtainhigh molecular weight polymer, it is preferred if the process is runwith little or no solvent (neat). Also in order to obtain high molecularweight, it is preferred if the monomer is highly purified. Thispurification can usually be accomplished by distillation. (For example,the monomer EVEOH[perfluoro(9,9-dihydro-9-hydroxy-3,6-dioxa-5-methylnon-1-ene)]may bedistilled through a spinning band column, boiling point about 78° C. at27 mm pressure. For best results the middle fractions should be used.)

When "another compound", as defined on page 7, lines 14-17, above, isused as the catalyst, the preferred temperature is about 80° C. to about150° C., more preferably about 100° C. to about 120° C. Since thepolymerization is exothermic, care should be taken to provide adequatecooling, especially when the polymerization is run neat.

When ™another compound™is used as the catalyst it is preferred if thecatalyst is about 0.1 to about 10 percent by weight, more preferablyabout 0.2 to about 4 percent by weight of the hydroxy fluorovinyl etherpresent.

The product polymers may be isolated by techniques well known to thoseskilled in the art, such as evaporation of solvent. Such techniques areillustrated in the Examples.

In preferred hydroxy containing fluorovinyl ethers used in the processR⁴ is --(CF₂)_(s) --, wherein s is 1 to 10; or R⁴ is --[CF₂CF(CF₃)O]_(t) (CF₂)_(u) --, wherein u is 1 to 10 and t is 1 to 20. In anespecially preferred embodiment t is 1 and u is 1, or s is 2.

This invention also concerns a cyclic ether of the formula ##STR3##wherein R⁴ is perfluoroalkylene and q is 2, 3 or 4. In preferred cyclicethers, n is 2. In other preferred cyclic ethers R⁴ is --(CF₂)_(s) --,wherein s is 1 to 10, and it is especially preferred if s is 2. Inanother preferred cyclic ether, R⁴ is --[CF₂ CF(CF₃)O]_(t) (CF₂)_(u) --,wherein u is 1 to 10 and t is 1 to 20, and it is especially preferred ift is 1 and u is 1. The cyclic ethers are made by the process describedimmediately above. The cyclic ethers are useful as lubricants. They mayalso be fluorinated to form perfluorinated cyclic ethers which areuseful as lubricants and heat transfer fluids (as described in copendingcommonly assigned application Ser. No. 07/713,926, filed of even datewith this application). The cyclic ethers of this invention aretherefore useful as intermediates for the production of suchperfluorinated cyclic ethers.

A polymer consisting essentially of the repeat formula --[CF₂ CFHOR⁴ CF₂CH₂ O]--, wherein R⁴ is perfluoroalkylene.

In preferred polymers R⁴ is --(CF₂)_(s) --, wherein s is 1 to 10; or R⁴is --[CF₂ CF(CF₃)O]_(t) (CF₂)_(u) --. wherein u is 1 to 10 and t is 1 to20. In an especially preferred embodiment t is 1 and u is 1, or s is 2.

These polymers are useful as lubricants, lubricant precursors,macromonomers and coatings. These polymers are made by the processdescribed immediately above.

A copolymer comprising the hydroxy containing repeat unit ##STR4##wherein p is 0 or 1, m is 0 to 10 and n is 1 to 20, provided that when mis 0, p is 0, and further provided that when m is greater than 0, p is1, and one or more other repeat units.

Such a repeat unit, which has a hydroxy contained within it, is usefulas a reactive site along the polymer chain to accomplish processes suchas crosslinking, or may change the surface characteristics of a polymerwhile leaving the bulk properties relatively unchanged. Thus in manycases the above repeat unit will be present in the polymer in onlyrelatively small amounts, about 0.001 to about 30 mole percent,preferably about 0.05 to about 15 mole percent.

It is especially useful in crosslinking relatively unreactive polymers,such as fluoropolymers. Thus it can be incorporated into polymerscontaining repeat units derived from monomers selected from the groupconsisting of tetrafluoroethylene; hexafluoropropylene and vinylidenefluoride; hexafluoropropylene, vinylidene fluoride andtetrafluoroethylene; ethylene and vinylidene fluoride; perfluoro(methylvinyl ether) and tetrafluoroethylene; perfluoro(methyl vinyl ether) andhexafluoropropylene; chlorotrifluoroethylene; ethylene andchlorotrifluoroethylene; vinylidene fluoride; tetrafluoroethylene andpropylene; tetrafluoroethylene and ethylene; tetrafluoroethylene andhexafluoropropylene; perfluoro-2,2-dimethyl-1,3-dioxole;perfluoro-2,2-dimethyl-1,3-dioxole and tetrafluoro-ethylene; vinylfluoride; tetrafluoroethylene andperfluoro[2-(fluorosulfonylethoxy)propyl vinyl ether]; and vinyl acetateand tetrafluoroethylene. In the immediately above listing of monomers,each of the monomer(s) between the semicolons represents a specificcopolymer of the hydroxy containing fluorovinyl ether with thatparticular monomer or combination of monomers. By "incorporated intopolymers" in the sentence above is meant that when the above polymers(and others not specifically mentioned) are formed by free radicalpolymerization, the appropriate amount of hydroxy containing fluorovinylether monomer is added to the polymerization reaction to becopolymerized with the other monomer(s). It will be noted that thepolymers above contain fluoromonomers. The term fluoromonomers means amonomer containing a vinyl group to which at least 1 fluorine atom isdirectly bound (i.e. has one or more vinylic fluorine atoms). Copolymersof the hydroxy containing fluorovinyl ethers with fluoromonomers, andoptionally other monomers, are preferred. Also preferred are copolymerswith vinyl esters, and especially preferred is vinyl acetate. Suchpolymers are useful for example, as molding resins (when plastic) andelastomers (where the "base" polymer is an elastomer).

These copolymers can be made by methods well known to those skilled inthe art. Further illustrations of typical polymerizations processes aregiven in the Examples.

In the following Examples, the following abbreviations and terms areused:

Bu --n-butyl

t-BuOK --potassium t-butoxide

dispersion factor --weight average molecular weight/number averagemolecular weight

DMF --N,N-dimethylformamide

DP --degree of polymerization (equal to Mn divided by the monomermolecular weight)

DSC --differential scanning calorimetry

EtOH --ethanol

EVE --methyl perfluoro (4,7-dioxa-5-trifluoromethyl-hept -8-enocite)

EVE alcohol --perfluoro (9,9-dihydro-9;-hydroxy-3,6-dioxa-5-trifluoromethylnon -1-ene)

EVEOH --perfluoro(9,9-dihydro-9-hydroxy-3,6-dioxa-5-trifluoromethylnon-1-ene

F-113 --1,1,2-trichloro-1,2,2-trifluoroethane

GC --gas chromatography

GPC --gel permeation chromatorgraphy

Me --methyl

Mn --number average molecular weight

MS --mass spectrum

M_(w) --weight average molecular weight

PDD --perfluoro(2,2-dimethyl-1,3-dioxole) (Can be made by methodsdescribed in U.S. Pat. Nos. 3,865,845, 3,978,030 and 4,393,227)

PMMA --poly(methyl methacrylate)

PPN --bis(triphenylphosphoranylidene)ammonium, [(C₆ H₅)₃ P--N═P(C₆ H₅)₃]⁺

TFE --tetrafluoroethylene

Tg --glass transition temperature

Tm --melting temperature

VAc --vinyl acetate

EXAMPLE 1 Preparation of9,9-Dihydro-9-hydroxy-perfluoro-(3,6-dioxa-5-methyl-1-nonene)(CF₂═CFO--CF₂ CF(CF₃)O--CF₂ CF₂ --CH₂ OH):

To a dry flask was charged EVE (211 g, 0.50 mole) in absolute ethanol(300 ml) with a magnetic stirring bar. Sodium borohydride (11.34 g, 0.30mole) was added slowly from a solid addition funnel. The reaction wassomewhat exothermic and the reaction pot was kept at ≦10° C. by externalcooling. After the addition of sodium borohydride was completed, thereaction mixture was stirred for 1 hr at room temperature. The potmixture was then dumped into an ice water (600 ml)/6N HCl (600 ml)mixture. The bottom product layer was separated, washed with water anddistilled to give the desired product as a clear, colorless liquid. Bp.68° C/25 mmHg. Yield: 168.7 g (85.6 %). H-1 NMR(CDC13): 4.00 (dt, J =1.0Hz, 13.5 Hz, 2H), 2.12 (s, br, 1H ); F-19 NMR (CDC13, F-11 internalstandard): -80.4 (s, br, 3F), -84.2 (s, br, 2F), -85.3 (m, br, 2F),-126.6 (t, J =14 Hz, 2F), -145.7 (t, J =21.8 Hz, 1F), -113.4, -113.7,-113.8, -114.2 (4s, 1F), -121.6, -112.1, -122.2, -122.7 (4t, J =5.2 Hz,1F), -135.3, -135.6, -135.9, -136.2 (4t, J =5.8 Hz, 1F).

EXAMPLE 2 Preparation of9,9-Dihydro-9-hydroxyperfluoro-(3,6-dioxa-5-methyl-1-nonene)

EVE (21.1 g, 0.05 mole) was dissolved in absolute ethanol (15 ml) at 0°C. In a separate flask was charged sodium borohydride (1.15 g, 0.03mole) in absolute ethanol (20 ml) at 0° C. The NaBH₄ /EtOH solution wasadded slowly into EVE/EtOH solution while the pot temperature was keptbetween 0° to 5° C. After addition, the reaction mixture was stirred for15 min at room temperature. The product was worked up as described inExample 1 and distilled to give the clear, colorless product 11.7 g(59.4% yield) as a liquid. Bp. 70° C./25 mmHg.

EXAMPLE 3 Preparation of7,7-Dihydro-7-Hydroxyperfluoro(3-Oxa-1-Heptene)(CF₂ ═CFO--CF₂ CF₂ CF₂--CH₂ OH)

To a dry flask was charged methyl perfluoro (5-oxa-6-heptenoate) (61.2g, 0.2 mole) in absolute ethanol (120 ml). Sodium borohydride (4.54 g,0.12 mole) was added slowly into the reaction solution via a solidadditional funnel while the temperature was kept at about 10° C. Themixture was allowed to stir at room temperature for 1 hr after theaddition of NaBH4 was completed. The mixture was then dumped into icewater/6NHCl (1:1 v/v, 500 ml) and worked up. The product was isolated byfinal distillation. 47.6 g (85.6% yield) of the desired product wasobtained as a clear, colorless liquid. Bp. 54°-55° C./30 mmHg. H-1 NMR(CDCl₃): 4.10 (t, J =14.5 Hz, 2H); 2.65 (s, br, 1H); F-19 NMR (188.24MHz, CDC13): -85.7(m, 2F), -123.4 (m, 2F), - 127.6 (s, br, 2F), -113.7,-114.1, -114.2, -114.5 (4m, 1F), -121.8, -122.3, -122.4, -122.9 (4t, J=5.6 Hz, 1F), -134.9, -135.2, -135.5, -135.8 (4t, J =5.6 Hz, 1F).

EXAMPLE 4 Homopolymerization of CF₂ ═CFO--CF₂ CF(CF₃)O -CF₂ CF₂ --CH₂OH:

Potassium t-butoxide (0.112 g, 0.001 mole) was dissolved in N,N-dimethylformamide(DMF) (10 ml) and was cooled to 0° C. The title vinyl etheralcohol (7.88 g, 0.02 mole) in DMF (4 ml) was added slowly into theabove solution via syringe. The reaction was maintained between at 10°to 25° C. via external cooling. After the addition was finished, themixture was stirred for 2 hrs at about 10° C., then warmed up graduallyto room temperature and was continued at ambient temperature for 6 hrs.The product mixture was dumped into ice water and was extracted withether. The ether layer was separated, washed thoroughly with water anddried over magnesium sulfate. Ether solvent was removed in vacuo and theproduct polymer was further dried under high vacuum. 4.24 g (53.8 %yield) of polymeric viscous oil was obtained. The weight averagemolecular weight was determined to be 4,100 with dispersion factor 1.51by GPC with PMMA as the reference standard. The structure of the productwas supported by its H-1 and F-19 NMR spectroscopic data.

EXAMPLE 5 Homopolymerization of CF₂ ═CFO--CF₂ CF(CF₃)O-CF₂ CF₂ --CH₂ OH

The title vinyl ether alcohol (7.88 g, 0.02 mole) was polymerized withpotassium t-butoxide (0.112 g, 0.001 mole) in DMF as described inExample 4. After warmed to room temperature, the reaction mixture wasstirred at ambient temperature for 48 hrs instead of 6 hrs. Afterworking up, the polymeric oil was determined to have weight averagemolecular weight 5,920 with a dispersion factor 1.74 by GPC with PMMA asreference standard.

EXAMPLE 6 Homopolymerization of CF₂ ═CFO--CF₂ CF₂ CF₂ --CH₂ OH

Potassium t-butoxide (0.112 g, 0.001 mole) was dissolved in DMF (10 ml)at 10° C. The alcohol substrate (5.56 g, 0.02 mole) in DMF (4 ml) wasadded slowly into the t-BuOK/DMF solution slowly via syringe. Afterstirring for 2 hrs at 10° C., the reaction mixture was warmed slowly toroom temperature. Some exotherm was observed when temperature reached25° C. The reaction mixture was cooled and kept stirring for 6 hrs atroom temperature. The product was then dumped into ice water and wasworked up as previously described. 4.13 g (74.3 % yield) of pale-yellowviscous polymeric oil was obtained. The weight average molecular weightof this polymer was determined to be 4,970 with dispersion factor 2.00by GPC by the use of PMMA as the reference standard.

EXAMPLE 7 Free Radical Copolymerization of EVE Alochol with TFE

In a shaker tube was charged EVE Alcohol (10 g, 0.0254 mole),1,1,2-trichloro-1,2,2-trifluoroethane (F-113) (60 g, 0.32 mole) and4,4'-bis(t-butylcyclo-hexyl)peroxy dicarbonate (0.05 g). The tube wassealed, cool-evacuated and tetrafluoroethylene (10 g, 0.1 mole) was thencharged. The tube was sealed again and was heated at 50° C., 60° C. and70° C. for 2 hrs respectively with shaking. The solvent was removed fromthe unloaded polymer solution and the polymer was finally dried in avacuum oven (ca. 150 mmHg) at 120° C. for 24 hrs. White polymer, 9.0 g,was obtained. The polymer has a Tm at 240° C. as measured by DSC. Thecomposition of this polymer was determined to be TFE/EVE alcohol =87/13(mole %) by F-19 high temperature NMR spectroscopy.

EXAMPLE 8 Free Radical Copolymerization of EVE Alcohol with TFE

In the shaker tube was charged EVE alcohol (10 g, 0.0254 mole), F-113solvent (20 g, 0.107 mole) and 4,4'-bis(t-butylcyclohexyl)peroxydicarbonate (0.03 g tube was sealed and cool-evacuated andtetrafluoro-ethylene was charged in. The tube was heated to 45° C. andthe pressure of tetrafluoroethylene maintained at 60 psi. The tube wasshaken for 6 hrs and was worked up as in Example 7. 3.3 g of the whitepolymer was obtained. This polymer has shown a Tg at 164° C. asdetermined by DSC, and have a composition of TFE/EVE alcohol =74/26(mole %) as determined by F-19 high temperature NMR spectroscopy.

EXAMPLE 9 Free Radical Copolymerization of EVE Alcohol and TFE

This polymerization was carried out with EVE alcohol monomer (4 g,0.0102 mole), F-113 (72 g, 0.417mole ),4,4'-bis(t-butylcyclohexyl)peroxy dicarbonate (0.05 g) andtetrafluoroethylene (20 g, 0.2 mole) in a shaker tube at 50° C., 2 hrs;60° C., 2 hrs and 70° C., 2 hrs. 17.3 g of white polymer was obtained.The polymer has a Tm at 318.3° C. as shown by DSC and has a compositionof EVE alcohol 98.5-99.0/1.5-1.0 (mole %) as determined by F-19 NMR.

EXAMPLE 10 Free Radical Copolymerization of EVE Alcohol and PDD

This polymerization was carried out with EVE alcohol (5 g, 0.0127 mole)and PDD (30 g, 0.123 mole) in F-113 (100 g, 0.533 mole) with4,4'-bis(t-butylcyclohexyl)peroxy dicarbonate (0.06 g) initiator underthe same temperature as described in Example 9. White polymer 6.3 g wasobtained after workup. This polymer has a Tg at 210° C. The compositionof this polymer was determined to be PDD/EVE alcohol =96.5/3.5, (mole %)by F-19 NMR.

EXAMPLE 11 Free Radical Copolymerization of EVE Alcohol, TFE and VAc

In the shaker tube was charged EVE alcohol (10 g, 0.0254 mole), VAc (40g, 0.465 mole), F-113 (120 g, 0.64 mole) and4,4'-bis(t-butylcyclohexyl)peroxy dicarbonate (0.1 g). The tube wassealed and tetrafluoroethylene (4 g, 0.04 mole) was added after the tubewas cooled and evacuated. The tube was resealed and was heated at 60° C.for 6 hrs. The resulting polymer solution was dissolved in acetone andprecipitated with ice water. The polymer was collected by filtration andwashed with water and was dried under nitrogen purge at ambienttemperature. White solid polymer 48.7 g was obtained. The polymer has aTg at 40.6° C. by DSC and the polymer has a composition of VAc/TFE/EVEalcohol =62.8/27.6/9.6 (mole %) as calculated from its H-1 & F-19 NMRspectroscopic data. The structure of the polymer was also supported byits IR spectrum.

EXAMPLE 12 Free Radical Copolymerization of EVE Alcohol, TFE and PDD

This experiment was carried out with EVE alcohol (2 g, 0.0051 mole), PDD(51 g, 0.209 mole) and tetrafluoroethylene (1 g, 0.01 mole) in F-113(165 g, 0.88 mole) by the use of 4,4'-bis(t-butylcyclo-hexyl)peroxydicarbonate initiator (0.2 g) in a shaker tube at 50° C., 60° C. and 70°C. for 2 hrs respectively. 44.9 g of white polymer was obtained afterworking up. This polymer has shown a Tg at 224.3° C. by DSC.

EXAMPLE 13 EVEOH Cyclic Dimer

A mixture of tetraglyme (5 mL) and oil-free potassium hydride (5 mg) wastreated dropwise with EVEOH (1.0 g, 2.5 mmol). GC analysis (25 m methylsilicone gum capillary column, 60°-250° C. at 20 deg/min) after 4 hshowed no starting material and several components with ca. 10 minretention time. The reaction mixture was treated with water, extractedwith F-113, and the extract was washed several times with water, dried,and evaporated to give 1.0 g of colorless oil. Kugelrohr distillation(0.2 mm, to 100 deg) gave ca. 100 mg of oil. ¹⁹ F NMR (acetone-d₆):-79.5 (m, CF₃), -82.2 to -85.0 and -85.3 to -87.0 (overlapping ABpatterns, OCF₂), -89.4 to -92.5 (m, upfield portion of overlapping ABpatterns), -122.8 to -123.8 (m, CF₂ CH₂), -143.0 to -143.8 and -144.6 to-146.4 (m, CFH and CF(CF₃)). GC/MS showed for the cyclic dimer a parention with m/z=787.974152 (calcd for C₁₆ H₆ F₂₆ O₆ =787.974922: for thecyclic trimer a parent ion with m/z=1181.952957 (calcd for C₂₄ H₉ F₃₉ O₉=1181.962383); for the cyclic tetramer a parent ion with nominalm/z=1579.

The reaction described above was repeated using glyme (5 mL) as solvent.After 18 h, work-up (dilution with ether, addition of water) andKugelrohr distillation (0.1 mm) gave 0.58 g, bp 80-92, and 0.13 g, bp140-155.

A larger scale reaction using 6.0 g EVEOH, 30 mg KH, and 35 mL glymeprovided 2.56 g of cyclic dimers.

EXAMPLE 14 Polymerization of EVEOH with Cs₂ CO₃

Cs₂ CO₃ (10 mg) and EVEOH (1.0 g) were placed in a vial, sealed, andheated in an oil bath maintained at 120° C. Within 1 hr, the mixture hadthickened considerably. The reaction mixture was maintained at 120° C.for 88 hr. ¹ H NMR (THF-d₈): 6.65 (d, J=52 Hz, CHF), 4.58 (t, J=13Hz,internal CF₂ CH₂ O), 3.90 (triplet J=ca 13Hz, CHF), 4.58 (t, J=13Hz,internal CF₂ CH₂ O), 3.90 (triplet J=ca 13Hz, terminal CH₂ O);integrated area of internal CH₂ O to terminal CH₂ O groups was ca. 55/1.Size exclusion analysis showed the major peak (90%) with Mn=27,200 andMw=57,900 using polystyrene standards. ¹⁹ F NMR featured internal CF₂CH₂ O(-123.6) and terminal CF₂ CH₂ O groups (-125.6) in relative areasof 126/1. No signals for residual trifluorovinyl groups were observed.NMR and size exclusion analyses were in reasonably good agreement andwere consistent with the desired linear condensation polymer (CF₂CHFOCF₂ CF(CF₃)OCF₂ CF₂ CH₂ O)_(n). TGA of a similarly prepared sampleshowed onset of thermal decomposition at ca. 300° C. (air) and 400° C.(N2). DSC exhibited Tg at -60° C.

EXAMPLE 15 Polymerization of EVEOH with Me₄ NCl

Me₄ NCl (2 mg) and EVEOH (1.0 g) were placed in a vial, sealed, andheated in an oil bath at 107° C. for 65 hr. ¹ H NMR analysis of thecolorless, viscous grease showed the ratio of signals at 4.6 ppm and3.90 ppm as ca. 60/1. The small amount of cyclic dimer formed (GCanalysis) was removed by kugelrohr distillation (up to 110° C./0.05 mm).19F NMR featured the internal/terminal CF₂ CH₂ O group ratio as ca.83/1. Size exclusion analysis showed the major peak with Mn=26,700 andMw=52,800, consistent with EVEOH condensation polymer, of the formulashown in Example 14.

EXAMPLE 16 Polymerization of EVEOH with PPNCl

PPNCl (5 mg) and EVEOH (1.0 g) were placed in a vial, sealed and heatedat 120° C. for 18 h r. ¹ H NMR analysis featured the ratio of 4.60/3.90signals as ca. 59/1 (assignments discussed in Example 14). ¹⁹ F NMRfeatured ratio of -123.7/-125.6 signals as ca. 75/1 Size exclusionanalysis featured the major component with Mn=20,200, Mw=37,800,consistent with the EVEOH condensation polymer.

EXAMPLE 17 Polymerization of EVEOH with Potassium Carbonate

K₂ CO₃ (30 mg) and EVEOH (1.0 g) were placed in a vial, sealed andheated at 50° C. for 0.5 hr and then at 100° C. for 18 hr. ¹⁹ F NMRshowed the signals described in Example 14 with additional signals at-121.6, -136.0, -137.4, -143.5 and -147.0. Size exclusion analysis hadMw=8570, Mn=6120.

EXAMPLE 18 Polymerization of EVEOH with Tetrabutylammonium Bicarbonate

Tetrabutylammonium bicarbonate was prepared as described below: Asolution of tetrabutylammonium chloride (3.0 g, 11.5 mmol) in methanol(25 mL) was treated with potassium carbonate (0.78 g, 5.7 mmol) andstirred for 18 hr. The mixture was filtered and stripped. Under drynitrogen, the residue was taken up in CH₃ CN, filtered, and partiallyevaporated. Ether was added, and the resulting solid was separated,triturated with ether, and filtered to give an off-white solid, mp90-115 deg. IR (nujol mull) featured a significant band at 1673 cm⁻¹.(Lit reference =Inorg. Chem., Vol. 28, p. 1231 (1989) for IRcomparison.)

A mixture of EVEOH (1.0 g) and tetrabutylammonium bicarbonate (10 mg)was prepared in a vial, sealed and heated to 80° C. for 15 min and then120° C. for 18 hr. ¹ H NMR analysis showed the ratio of in-chain CH₂O/terminal CH₂ OH groups to be ca. 50/1. ¹⁹ F NMR was likewise in accordwith the EVEOH condensation polymer. Size exclusion analysis showedMw=34, 500; Mn=17, 200.

EXAMPLE 19 Polymerization of EVEOH with Bu₄ NCl

EVEOH (1.0 g) and tetrabutylammonium chloride (2 mg) were placed in avial, sealed and heated to 107° C. for 65 hr. ¹ H NMR analysis showedthe ratio of in-chain CH₂ O/terminal CH₂ OH groups to be ca. 60/1. Sizeexclusion analysis showed Mw=46,700; Mn=24,000. Tg=ca. -60° C.

EXAMPLE 20 Polymerization of EVEOH with (PPN)₂ CO₃

PPN carbonate was prepared as follows: Silver carbonate (1.38 g) wasadded to a solution of PPN chloride (5.74 g) in dry acetonitrile (40 mL)and the resulting mixture was stirred vigorously for 2 hr, filtered andevaporated to give 3.18 g of light tan solid. The product was trituratedwith THF and filtered to give 2.3 g of off-white solid. IR (KBr) showeda band at 1640 cm⁻¹.

EVEOH (1.0 g) and PPN carbonate (2 mg) were mixed in a vial and heatedat 50° C. (20 min), 80° C. (30 min), and 120° C. for 16 hr. NMR spectrawere in accord with EVEOH homopolymer, and indicated DP ca. 100-120.Size exclusion analysis showed Mw=52,100, Mh=22,900.

EXAMPLE 21 Polymerization of EVEOH with Cesium Fluoride

EVEOH (1.0 g) and cesium fluoride (4 mg) were mixed in a vial, sealed,and heated for 18 hr. ¹⁹ F NMR showed the ratio of internal CF₂ CH₂/terminal CF₂ CH₂ OH groups to be ca. 57/1. Size exclusion analysisshowed Mw=31,100; Mn=16,700.

EXAMPLE 22 Polymerization Using Purified EVEOH

A sample of EVEOH (7.85 g, 19.9 mmol) was treated in small portions withbromine (3.2 g, 20 mmol), controlling the temperature at 15-22 deg. Whenthe reaction was judged to be complete by GC analysis, excess brominewas removed under a stream of nitrogen and the product was isolated bykugelrohr distillation, 50° C./0.2 mm, providing 8.70 g. ¹⁹ F NMR(THF-d₈): -164.13 (m, 2F, CF₂ Br), -72.2 (apparent doublet of quartets,J=24, J=9 Hz) and -72.55 (apparent doublet of quartets J=23, 9 Hz, 1F,CFBr for two diastereomers), -80.5 to -86.2 (group of overlapping ABpatterns, 4F, OCF₂), -79.4 (apparent quartet, J=9, 3F), -125.38 (t,J=14.8 Hz, 2F), -145.4 (m, 1F, tertiary CF), consistent with the desireddibromo alcohol.

A slurry of activated zinc dust (2.72 g, 41.6 mmol) and DMF (15 mL) wastreated in portions with dibromoethane (1.05 g, 5.6 mmol) and stirredfor 0.5 hr at ambient temperature. DibromoEVEOH (distilled, 10.0 g, 18mmol) was added and the mixture was stirred for 1.25 hr, filtered, andthe filtrate was added to water. The lower layer was separated, washedwith water, and dried (MgSO₄). Traces of remaining water were removed bycontact with activated sieves, and the product was kugelrohr distilled.NMR analysis did not detect contamination by other fluorinated alcohols.

A sample of the above EVEOH (1.0 g) and Cs₂ CO₃ (4 mg) were mixed andprocessed as described in Example 14 (100° C./1 hr, 120° C./15 hr).Endgroup analysis by NMR suggested a value of DP above 200. Sizeexclusion analysis showed slightly higher values of Mw (65,500) and Mn(28,500) than were determined for other examples.

Although preferred embodiments of the invention have been describedhereinabove, it is to be understood that there is no attempt to limitthe invention to the precise constructions herein disclosed, and it isto be further understood that the right is reserved to all changescoming within the scope of the invention as defined by the appendedclaims.

What is claimed is:
 1. A cyclic ether of the formula ##STR5## wherein R⁴ is perfluoroalkylene or perfluoroalkylene containing one or more ether oxygen atoms, and q is 2, 3, or
 4. 2. A cyclic ether as recited in claim 1 wherein said q is
 2. 3. A cyclic ether as recited in claim 1 wherein said R⁴ is --(CF₂)_(s) --, wherein s is 1 to
 10. 4. A cyclic ether as recited in claim 3 wherein said s is
 2. 5. A cyclic ether as recited in claim 1 wherein said R⁴ is --[CF₂ CF(CF₃)O]_(t) (CF₂)_(u) --, wherein u is 1 to 10 and t is 1 to
 20. 6. A cyclic ether as recited in claim 5 wherein said t is 1, and said u is
 1. 7. A cyclic ether as recited in claim 6 wherein said q is
 2. 